JPS59152451A - Manufacture of toner for developing electrostatic charge image - Google Patents

Abstract

PURPOSE:To obtain a toner having a narrow grain size distribution, high fixability, a significant antioffsetting effect and favorable blocking properties by suspension-polymerizing a specified monomer system in a specified dispersion medium. CONSTITUTION:A monomer system contg. a polymerizable monomer such as styrene, an anionic (co)polymer such as a (meth)acrylic acid polymer or a styrene-(meth)acrylic acid copolymer and a hydrocarbon compound such as paraffin wax or further contg. a dye or a pigment and other additives is suspension- polymerized in a dispersion medium contg. a cationic dispersant such as positively chargeable hydrophilic colloidal silica treated with a silane treating agent contg. nitrogen in the form of an amino group or the like. The titled toner is manufactured by the polymn. The toner has a very narrow grain size distribution, high fixability, a significant antioffsetting effect and favorable blocking properties as well as high flowability, high developing power and superior wear resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a toner for developing electrostatic images, and more specifically, the present invention relates to a method for producing a toner for developing electrostatic images, and more specifically, the present invention relates to a method for producing a toner for developing an electrostatic image, and more particularly, dyes and pigments and other additives are added to polymerizable monomers as required, and the monomers are The present invention relates to a method for producing toner for developing electrostatic images, which comprises suspending a toner in a dispersion medium and polymerizing the same.

Conventionally, toners can be produced by melt-mixing colorants and other additives in a thermoplastic resin, uniformly dispersing the mixture, and then using a pulverizer and a classifier to produce an excellent toner with a desired particle size. There are species restrictions.

That is, the toner obtained using the pulverization method must have some brittleness so that the material is somewhat susceptible to pulverization. However, things that are too fragile
If the toner is too finely powdered, it is necessary to cut the fine powder which is not worth it in order to obtain a toner with an appropriate particle size distribution, which increases the cost. Furthermore, in some cases, the toner is further pulverized in the developing device of a copying machine. In addition, if a material with a low melting point is used to improve heat fixability or a liquid material with constant pressure is used, a fusion phenomenon may occur in the crushing equipment or classification equipment, and continuous production may not be possible. A coincidence occurs.

Other requirements for the toner are that it has triboelectric properties suitable for development, that it forms an excellent image, that there is no change in performance when left unused, and that it does not coagulate (e.g., solidification).
Examples include applying appropriate heat and not applying pressure. In particular, during fusing, the offset phenomenon in which toner adheres to the fusing roller and is retransferred onto the next coffee paper is a constant problem. Painting has been done. However, in recent years, there has been a lot of sexual harassment in Bokusuichi.
, polyethylene resin, etc., and do not apply any peeling agent to the fixing roller.
methods to prevent this have become commonplace. However, although this method is sufficiently effective in preventing off-loading, it requires an auxiliary constant 72R roller cleaning device and cannot be used in large quantities without maintenance. Therefore, attempts have been made to add more polyolefin y to the dog t1, or to use a polyolefin with a lower melting point, but these have resulted in fusion in the crusher or classifier, or Because the polyolefin is exposed, the film may sag or the fluidity may deteriorate, significantly reducing developability.

In order to overcome the drawbacks of the pulverization method, a method for producing toss by a suspension polymerization method was proposed.

In other words, since this method does not involve any pulverization process, brittleness is not required, and since the material is spherical in shape, it has excellent fluidity, and as a result, triboelectric charging is uniform.

However, it is technically difficult to polymerize 'lx in a stable suspension system with good coalescence, and to obtain fine polymer particles with a uniform particle size distribution through polymerization. Therefore, the polymerizable monomer system is in water! During 8fA polymerization, a suspension stabilizer is used to prevent coalescence of polymer particles as the polymerization progresses.

Generally, suspension stabilizers include elutable finely powdered inorganic compounds such as BaSO4, CaSO4, MgCO3, BaC
Slightly soluble salts such as O3, CaCO2, Ca3(PO4)2, diatomaceous earth, talc, silicic acid, inorganic polymers such as clay, metal oxide powders, water-soluble polymers such as polyvinyl alcohol, gelatin, starch and so on.

Further, stirring also affects the stability of polymerization and the size of particles. High-speed stirring stabilizes polymerization, but the particles become smaller than necessary. Conversely, if the mixture is stirred at low speed, it may gel and particles may not be obtained. Therefore, it is necessary to choose appropriate conditions.

However, even with these methods, it is difficult to obtain fine particles having a particle size that is satisfactory as a toner, that is, a number average diameter of about 10 to 20 μm.

This is because, in the end, there is no sufficient way to prevent union. Therefore, in the combination of a polymerizable monomer and an inorganic dispersant, the interface of the polymerizable monomer particles is anionically charged by the anionic polymerizable monomer, while the inorganic dispersant The inorganic dispersant coats the surface of the polymerizable monomer particles with a strong cation that is opposite to that of the particles and completely uniformly coats the surface of the polymerizable monomer particles to prevent coalescence, and the number average diameter is 10 to 20μ. A method has been proposed to obtain particles of approximately

However, even with this method, it cannot be said that the diameter is sufficiently satisfactory as a toner. This is because it is more preferable that the toner particle size distribution is narrower. That is,
When the particle size becomes uniform, the amount of charge on each particle becomes almost the same, which makes it possible to obtain a stable image. The narrower the particle size distribution, the more stable the image, the better the reproducibility of fine lines, and the less fogging.

Furthermore, it is very difficult for the toner produced by this method to satisfy the contradictory properties of excellent properties, fixability, solidity, printing properties, and developability. The toner produced by this method has aniositic groups gathered on the particle surface, but since the entire polymer is almost homogeneous, it is necessary to reduce the molecular weight and lower the Tg (glass transition point) in order to improve heat fixability. The roll and drop properties deteriorate, and this is also reflected in development, resulting in poor image quality.

On the other hand, if high molecular weight, crosslinking, etc. are carried out in order to improve the thermal fixing properties, the heat fixing properties will deteriorate, resulting in a vicious cycle.

Therefore, one or more types of polymerizable precipitate,
If necessary, the system containing dyes and pigments, polymers, and other additives is suspended in a dispersion medium in which a cationic dispersant is dispersed, and in the polymerization system, the anionic polymer or the polymerizable monomer is added to the polymerizable monomer. A method has been proposed in which a copolymer is contained and polymerized.

Although not to be taken by theory, when an anionic polymer/monomer or a water-repellent organic acidic compound is added to the monomer system in the above method, these substances may be present on the surface of the suspended particles. It is thought that the aggregated monomers are slightly distributed from the monomer system into the dispersion medium system, making the interface between the particles and the dispersion medium uncertain, which makes the suspended particles a little unstable, and the particle size distribution cannot be said to be sufficiently narrow. reactor. This is not distributed at all from the quantitative system into the dispersion medium system. This is because it has a high molecular weight. As a result, the interface between the suspended particles becomes firm and stable, making it easier for the particle sizes to become uniform.

In particular, anionic polymers or copolymers gather on the surface of suspended particles, forming a kind of shell-like structure.
The resulting particles become pseudo force cells.

That is, irrespective of the initial polymerization of the polymerizable monomer, a resin having a desired degree of polymerization can be used as the anionic polymer or copolymer for the shell. Therefore, the interior is polymerized to a relatively low molecular weight material with excellent fixing properties, and the anionic polymer or copolymer in the shell is a relatively high molecular weight material with good developing properties. ,
A resin with excellent wear resistance can be used.

By the above method, it is possible to obtain a toner that satisfies the needs of practical use; however, there are many additional requirements placed on the toner. That is, it is strongly desired that fixing can be carried out in a more energy-saving manner without deteriorating the developability, smoothness, flowability, and abrasion resistance properties.

Therefore, an object of the present invention is to provide a novel method for producing a toner for developing an electrostatic image using such suspension polymerization.

Furthermore, the present invention provides a method for producing a toner for developing electrostatic images having a very narrow particle size distribution.

Furthermore, the present invention provides a method for producing and using a toner that has good fixing properties, good offset properties, and also good roll and fall properties.

Furthermore, the present invention provides a method for producing a toner for developing electrostatic images that has good fluidity and good developability.

Furthermore, the present invention provides a method for producing an electrostatic image developing toner having good abrasion resistance.

That is, a system containing one or more types of polymerizable monomers, dyes and pigments, polymers, and other additives as necessary is suspended in a dispersion medium in which an anionic polymer is dispersed, This objective can be achieved by adding a cationic polymer or copolymer and a hydrocarbon compound to the polymerizable monomer in the polymerization system and polymerizing the mixture.

Although not bound by theory, hydrocarbon compounds are hydrophobic and have low molecular weights, so they are difficult to mix with cationic polymers that have polar groups and large molecular weights. It is pushed into the inside of the toner without coming out. Then, when it settles, it comes out from the inside,
Significantly improves fixing and offset properties. At this time, the hydrocarbon compound is thought to function as a plasticizer, a lubricant, and an oil effect.

The hydrocarbon compound used in the present invention is preferably a paraffin or polyolefin having carbon of C6 or more, and examples include paraffin wax (Nippon Oil Co., Ltd.), Ba-Rabnoy 1.17 wax (Nippon Seisou Co., Ltd.), microwax (
Nippon Oil), Microcrystalline wax (Japanese wax), PE-130 (Heshist), Tamoshi Hiwax l
10P (Mitsui Petrochemical), Tamashii High Wax 220P (
Mitsui Petrochemicals), Tamaoshi Hiwax 660P (Mitsui Petrochemicals), etc., and rosefish is particularly preferred.

Examples of the anionic polymers used in the present invention include anionic polymerizable monomers, 2-acrylamido-2-methyldilopacysulfonic acid, N-methyl0-acrylamide, methacrylic acid, acrylic acid, and methacrylic acid-2- Shidoro diethyl methacrylate, 2-shidoro+shidorohiru methacrylate, nutacrylic acid acid methacrylate, polypropylene L/citalicol 7-methacrylate, polyethylene citalicol 7-methacrylate, methacrylic IL/mtetra-methacrylic acid, drofurfuryl, Acid phosphor diethyl methacrylate, male anhydride, hydroxyl group of heptacid, etc., carboxyl group, sulfur group,
, a polymer of monomers containing an I acid group, a phosphoric acid group, and an acid anhydride,
Or a copolymer with one or more of the following monomers, such as styrene, ○-methylstyrene, P-methylstyrene, 2,4-dimethylstyrene, P-n-dutylmethylstyrene, P-tert -Methylstyrene, P-n.
Styrenes such as dotyl styrene, P-riO styrene and P-phenylstyrene, vinylnaphthalenes, ethylene unsaturated t, such as polystyrene, iso-dethylene υ, etc.
Noolefins; vinyl esters such as vinyl chloride, dinylacetate, dinyl butyrate, be/hinyl soate; methyl acrylate, ethyl acrylate, ln-butyl acrylate, isobutyl acrylate, dibutyl acrylate pill, n-octyl acrylate, dodecyl acrylate, lauryl acrylate, 2-ethyl acrylate, stearyl acrylate, 2-ethyl acrylate, phenyl acrylate, α-methyl acrylate, methacryl Methyl methacrylate, ethyl methacrylate, O-pil methacrylate,
n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate,
α-Methyredialiphatic sonocarboxylic acid esters such as stearyl methacrylate, phenyl methacrylate, dimethyl atrinoethyl methacrylate, diethyla trinoethyl methacrylate, acrylonitrile, methacrylonitrile,
Acrylic acid or methacrylic acid derivatives such as acrylamide; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether;
Vinylketoshis such as vinyl methyl keto υ, vinyl heshisilgatoshi, methyl isoduroben, and ruketoshi; N-pinylhyrol, N-jinyl-rubasol, N-vinyl 1
Examples include N-vinyl compounds such as ``sideol'' and N-vinyl hydride.

Examples of the polymerizable monomer used in the present invention include styrene, ○-methylstyrene, P-methylstyrene, 2.4
-dimethylstyrene, P-n-butylstyrene, P-
Styrenes such as tert-butylstyrene, P-n dodecylstyrene, P-chlorostyrene, P-phenylstyrene, vinyl naphthalenes, ethylestyrene, polystyrenes,
Polyesters such as isoduchireshi; vinyl esters such as vinyl chloride, vinyl acetate, dinyl butyrate, and vinyl chloride; methyl acrylate, ethyl acrylate, n-butyl acrylate , isobutyl acrylate, proacrylate.

pill, n-octyl acrylate, dodecyl acrylate,
lauryl acrylate, 2-ethyl acrylate,
stearyl acrylate, 2-90 ethyl acrylate,
Phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, ethyl methacrylate, dihylic methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, methacrylic acid α-Methyredialiphatic t-nocarpocarbons such as lauryl, 2-ethyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethyl atrinoethyl methacrylate, diethyla trinoethyl methacrylate, I acid esters, acrylic acid nitrile, etc. Acrylic acid or methacrylic acid derivatives such as methacrylic acid nitrile and acrylamide; Vinyl ethers such as di-nyl methyl ether, vinyl ethyl ether, and di-nylysodbutyl ether; Nilketo V
U; N-vinylhyrol, N-vinylcarbacil, N
-N- such as vinylisidol, N-vinylhylorides, etc.
Examples include vinyl compounds.

One or more types of these may be used.

Further, one or more of these polymers may be contained in the polymerizable monomer.

Examples of the polymerization initiator used in the present invention include aisobisisodithyronitrile (AIBM), penzoylhydronitrile side, methyl ethylketoxyhydronitrile side, isodurohilpero + dicarbonate, + yumeshi hydroperioside, 2.4 - It can be carried out using a dichloride side, a lauroyl side, etc.

In the present invention, a crosslinked polymer may be formed using a crosslinking agent.

For example, dimethylbenzene, divinylnaphthalene and derivatives thereof, diethylene carboxylic acid such as diethylene glycol methacrylate, triethylene glycol methacrylate, ethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, etc.
, I acid ester, 1,2-dichlorodiglycol, 1,
Common crosslinking agents such as 3-dutasidiol can be used as appropriate.

Examples of the cationic dispersant include hydrophilic positively charged colloidal silica treated with a silica treatment agent containing nitrogen such as tri-aluminum oxide and amino groups.

Generally known dyes and pigments can be used as appropriate in the present invention. Furthermore, carbon black and magnetic materials can also be used. In particular, magnetic materials should be surface-treated.

The suspension method uses a monomer system in which a polymerization initiator, an aniosic polymer or its copolymer, monomers and additives, dyes and pigments, crosslinking agents, etc. are uniformly dissolved or dispersed, and a suspension stabilizer is added. The mixture is dispersed in a dispersed phase, that is, a continuous phase, using a conventional stirrer, a boiler, a bodizer, or the like. Preferably, the stirring speed and time are adjusted so that the monomer droplets have the desired size of toner particles, generally 30 μm or less, and after that, this state is maintained approximately by the action of the dispersion stabilizer. Stirring may be carried out to the extent that sedimentation of particles is prevented.

Polymerization is carried out by setting the polymerization degree appropriately. After the reaction is completed, the generated toner particles are processed through washing, filtration, dication,
Collect and dry by a suitable method such as centrifugation.

All known methods can be used to develop this toner. For example, two-component development methods such as cascade method, magnetic brushing method, microtony, and I-di method; conductive-component development method, insulating-component development method, di1'7shi, and :7di development. One-component development method containing a magnetic material such as powder cloud method and fur brush method; Non-magnetic component development method in which the toner is held on the toner carrier by electrostatic force and transported to the developing section for development. Laws, etc. can be mentioned.

Example 1 The sample was heated to 70 DEG C., and the copolymer, paraphyte wax, initiator, etc. were dissolved in methylene chloride. TK this
The mixture was mixed for about 5 minutes while being heated to about 60° C. in a container equipped with a mid-day shear mixing device such as a Ho-Shichimisasu (Tokushu Kika Kogyo M).

Separately 1000 cc of water iCH2N-GoNHCH2C
Hydrophilic positively charged silica treated with H2CH2-8i-(O02Ha,)s, + was dispersed at 42°C, heated to about 60°C, and the above Nanatsuma was stirred with a TK Hoshichisangyu saas. The mixture was added and stirred at 4000 rpm for about 1 hour. Thereafter, this mixed system was stirred using a paddle blade to complete the polymerization. After removing the dispersant, the product was washed with water, filtered, and dried to obtain a toner.

The obtained toner had a number average diameter of 9.4 μm, a number distribution of 6.3571 or less, 18%, and a volume distribution of 20.2 μm.
m or more was 1% (Coulter Calasiter, Avertise iooμ).

This was compared with Comparative Examples 1 to 3, which were made using the same method but had different compositions. The other compositions of the comparative example are the same as those of the example.

Images were created by mixing Iron Powder Ceria EFV 250/400 (Japan Iron Powder) and toner to a toner concentration of 10 wt % to form a developer, and developing with a copying machine NP5500. Further, the fixing property test was carried out at 0.degree. C. using a PC-10 sterilizer without applying a mold release agent such as silicone oil. Fluidity was determined by visual observation in an actual developing device.

Regarding abrasion resistance, we separated the continuous image + series from the toner, and examined the amount of toner that adhered to the +1-free P-, that is, the generally referred to as specide 1-ner.
On a 5-point scale, from very little ○ to very often ×
separated up to. This roughly corresponded to the image quality of continuous image durability.

Example 2 The above material was prepared in the same manner as in Example 1 to obtain a toner. The obtained toner had a number average diameter of 8.7μ and a number distribution of 6.
20% had pain of 35 μm or less, and 0% had pain of 20.2 μm or more in volume distribution (Coulter Calacita, Aperture 1).
00μ.

As a comparative example, the following 1-ner was prepared and compared in the same manner as in Example 1.

The image was produced using an NP-400RE copying machine, and the fixing device of the same machine was used for fixing.

Example 3 A toner was prepared in the same manner as in Example 1.

A toner of a comparative example was prepared in the same manner as in Example 1.2 and compared.

Images are produced by a method in which toner is held on a toner carrier by electrostatic force, transported to a developing section, and developed, using a toner that does not contain any magnetic material without mixing serif particles. went.

The fixing property was measured using a heated roller constant fixer (PC-10 Copy)7, and the abrasion resistance was measured in the same manner as in Example 2.

Example 4 A toner was prepared in the same manner as in Example 1.

Comparative toners were prepared and compared in the same manner as Examples 1 to 3.

The developing method here was the same as in Example 3. Fixing properties were tested using a pressure fixing device using a rigid roller.

Abrasion resistance is the same as in Example 3.

Claims (1)

[Claims] An electrostatic charge image characterized by polymerizing a heptamer system containing a polymerizable monomer, an aniositic polymer or copolymer, and a hydrocarbon compound by suspending it in a dispersion medium containing a cationic dispersant. A method for manufacturing toner for development.